Damage assessment critical to Afghanistan mission

Following two nights of missile strikes and bombing on Afghanistan, the critical task of assessing the damage caused by the US-led attacks has begun.

Intelligence about the result of the attacks is crucial to the US for a number of reasons. Full scale air operations can only begin if the air defences have been destroyed and any future ground troops must also know which military facilities remain. Additionally, early knowledge of any civilian casualties will help diplomatic efforts to keep Islamic countries in the coalition against international terrorism.

For these reasons, the US and its allies are now using every tool at their disposal, from satellites in space to agents on the ground, to assess the impact of the attacks.

On Monday night, the US kept up its assault on Taliban military and strategic targets. It also hit more training camps of the Al-Qaeda network, headed by Osama Bin Laden - the prime suspect for the terrorist atrocities of 11 September.

Ten bombers (stealth B2s and B-1Bs) were launched from the ground and 10 strike aircraft from aircraft carriers in the Arabian Sea. Tomahawk cruise missiles were also launched from naval vessels. Targets in Kabul, Kandahar and the airport at Mazer-i-Sharif were reported hit. The operation was less intense than Sunday night when 50 cruise missiles were launched at 30 sites.

Missile accuracy

The general accuracy of Tomahawk cruise missiles - being fired from the Arabian Sea, 1000 kilometres away - is uncertain. The US claims they are 90 per cent accurate, but this figure cannot be independently verified.

Duncan Lennox, editor of Jane's Strategic Weapons Systems thinks that 80 per cent accuracy is about the best that can be hoped for, even for large targets such as barracks or weapons factories. For smaller targets such as tanks or groups of tents, he thinks accuracy is "a lot lower."

Some data on the success of strikes can be obtained from space. As New Scientist reported on 4 October, every inch of Afghanistan is imaged every week by satellites. Computers can compare and contrast images to spot changes.

However, even at best satellites only pass over a particular spot twice a day, so they cannot reveal short term changes. Also, images are impossible if it is cloudy.

Spy planes

Closer to Earth are high altitude spy planes such as the crewed U2S or uncrewed RQ-4A Global Hawk. Both fly at around 20,000 metres (65,000 feet) and have high resolution, synthetic aperture radar systems that can produce photographic quality images through cloud or at night. They also have optical and infrared cameras.

Nick Cook, aerospace consultant for Jane's Defence Weekly says that the Global Hawk is not officially due to go into service for a year or two. However, he believes, "it is not unreasonable to expect that it is being used".

At even lower altitudes - about 7600 m (25,000 ft) - the US could use F18 fighters with real time video images beamed back to command centres or unmanned, slow-flying Predator spy planes. The Predator can also use lasers to 'light-up' targets for bombers, but one was shot down by the Taliban in late September.

False image

Despite the deployment of extensive hardware, mistakes have been made in the past. For example, in the Gulf war there were occasions when a target was believed to be destroyed, but when ground troops arrived, they found it intact.

Sometimes a bomb landing beside a target can shower it with so much debris that it looks like it has been destroyed, says Lennox.

In addition, the Serbs in Kosovo sometimes deliberately made it look like a target had been destroyed when it had not.

"It is very difficult to be absolutely sure that you've hit a target until you go in on the ground," says Cook. Target surveillance may be one of the most important jobs of special forces troops inside Afghanistan in the current stage of the campaign.

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